Considerations in the Phase-Out of Halon Total Flooding Fire Extinguishment Agents

Abstract

Deciding on a fire protection strategy when replacing halon fixed-flood extinguishment or inerting systems in existing E&P facilities or for new designs can be challenging, since the technology and public policy (regulations) are changing so rapidly. To further complicate decision-making, performance data for alternative fire fighting technologies are sometimes reported selectively or do not completely reflect fire risks in E&P industry applications. To assist in this decision-making process, the Halon Issues Sub-Committee of the Oil Industry International Exploration and Production Forum (E&P Forum) has issued a series of technical guidance reports (Ref. 7, 8, 9, 10) on considerations for halon phase-out. The considerations presented in this paper, from those E&P Forum guidance reports. are intended to assist in the process of halon phase-out and the selection of alternative and replacement fire fighting strategies. The considerations cover: regulatory trends which may influence agent selection; risk assessment; inherent fire safety design principles (Ref. 7); incipient fire condition detection and manual response; halon-like gases; water mist systems; inert gas flood systems; halon banking; and emerging fire fighting technology. Introduction For almost three decades, the halon group of chemicals (i.e., halocarbons containing fluorine, chlorine, and bromine) has been — in fire fighting terms — such a panacea that they were used widely throughout the world and across most industries. However, the chlorine and bromine in halons have been identified as potential contributors to the depletion of the stratospheric ozone layer. International concern over the effects of halocarbons on the ozone layer led to the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer and its subsequent revisions in June 1990 and November 1992. Resulting national regulations to phase out production — and in some countries, use — of halons, made after the discovery of their deleterious environmental effects, were perceived to leave a large gap in the fire fighter's armory. Such were the almost magical properties of halon that considerable effort has been expended trying to develop "drop-in" replacements, with particular emphasis on total flood applications. It is manifest that any halon replacement (halon-like) or alternative (everything else) should have the same characteristics as halon without potential adverse environmental effects. The main characteristics of halon that are looked for in a replacement or alternative include:–Non-toxic to humans at the design concentration–A clean extinguishant (no residue)–Rapid knock-down of flames–Not electrically conductive–Low design extinguishing concentration–Suitability for inerting applications–Compact and long-term agent storage The paper concludes that environmentally benign fire extinguishing techniques can be used in many E&P industry applications. Anthropogenic (man-made) fire extinguishing gases that accumulate in the atmosphere should only be used where required by law or are the only cost effective and people-safe option. The challenge for the E&P operator is to select an appropriate fire-protection strategy confronted by often confusing claims, selective reporting of fire test results, rapidly changing technology, and environmental regulations as well as limited real fire fighting experience with some of the new technologies. P. 657